<template>
  <div class="play">
    <!-- 模糊背景(靠样式设置), 固定定位 -->
    <div class="song-bg" :style="`background-image: url(${data.songInfo && data.songInfo.al && data.songInfo.al.picUrl
      }?imageView&thumbnail=360y360&quality=75&tostatic=0);`"></div>
    <!-- 播放页头部导航 -->
    <div class="header">
      <van-icon name="arrow-left" size="20" class="left-incon" @click="router.back()" />
    </div>
    <!-- 留声机 - 容器 -->
    <div class="song-wrapper">
      <!-- 留声机本身(靠css动画做旋转) -->
      <div class="song-turn ani" :style="`animation-play-state:${data.playState ? 'running' : 'paused'}`">
        <div class="song-img">
          <!-- &&写法是为了防止报错, 有字段再继续往下访问属性 -->
          <img style="width: 100%" :src="`${data.songInfo && data.songInfo.al && data.songInfo.al.picUrl
            }?imageView&thumbnail=360y360&quality=75&tostatic=0`" alt="" />
        </div>
      </div>
      <!-- 播放按钮 -->
      <div class="start-box" @click="audioStart">
        <span class="song-start" v-show="!data.playState"></span>
      </div>
      <!-- 播放歌词容器 -->
      <div class="song-msg">
        <!-- 歌曲名 -->
        <h2 class="m-song-h2">
          <span class="m-song-sname">{{ data.songInfo.name }}-{{
            data.songInfo && data.songInfo.ar && data.songInfo.ar[0].name
          }}</span>
        </h2>
        <!-- 歌词部分-随着时间切换展示一句歌词 -->
        <div class="lrcContent">
          <p class="lrc">{{ data.curLyric }}</p>
        </div>
      </div>
      <!-- 留声机 - 唱臂 -->
      <div class="needle" :style="`transform: rotate(${needleDeg});`"></div>
    </div>
    <!-- 播放音乐真正的标签
      看接口文档: 音乐地址需要带id去获取(但是有的歌曲可能404)
      https://binaryify.github.io/NeteaseCloudMusicApi/#/?id=%e8%8e%b7%e5%8f%96%e9%9f%b3%e4%b9%90-url
     -->
    <audio ref="audio" preload="true" :src="`https://music.163.com/song/media/outer/url?id=${data.id}.mp3`"></audio>
  </div>
</template>

<script>
// 获取歌曲详情和 歌曲的歌词接口
import { SongDetailAPI, SonglyricsAPI } from '@/api'
import { reactive, onMounted, getCurrentInstance, computed, ref } from 'vue'
import { useRoute, useRouter } from "vue-router";
export default {
  // components: {
  //   [Icon.name]: Icon,
  // },
  // computed: {
  //   needleDeg() { // 留声机-唱臂的位置属性
  //     return data.playState ? '-7deg' : '-38deg'
  //   }
  // },
  setup() {
    let route = useRoute()
    let router = useRouter()
    let currentInstance = getCurrentInstance()
    const audio = ref(null)
    const data = reactive({
      playState: false, // 音乐播放状态(true暂停, false播放)
      id: route.query.id, // 上一页传过来的音乐id
      songInfo: {}, // 歌曲信息
      lyric: {}, // 歌词枚举对象(需要在js拿到歌词写代码处理后, 按照格式保存到这个对象)
      curLyric: '', // 当前显示哪句歌词
      lastLy: '' // 记录当前播放歌词
    })
    const needleDeg = computed(() => {
      // 留声机-唱臂的位置属性
      return data.playState ? '-7deg' : '-38deg'
    })
    const getSong = async () => { // 获取歌曲详情, 和歌词方法
      const res = await SongDetailAPI(data.id)
      data.songInfo = res.data.songs[0]
      // 获取-并调用_formatLyr方法, 处理歌词
      const lyrContent = await SonglyricsAPI(data.id)
      const lyricStr = lyrContent.data.lrc.lyric
      data.lyric = _formatLyr(lyricStr)
      // 初始化完毕先显示零秒歌词
      data.curLyric = data.lyric[0]
    }
    const _formatLyr = (lyricStr) => {
      // 可以看network观察歌词数据是一个大字符串, 进行拆分.
      let reg = /\[.+?\]/g
      let timeArr = lyricStr.match(reg) // 匹配所有[]字符串以及里面的一切内容, 返回数组
      //console.log(timeArr); // ["[00:00.000]", "[00:01.000]", ......]
      let contentArr = lyricStr.split(/\[.+?\]/).slice(1) // 按照[]拆分歌词字符串, 返回一个数组(下标为0位置元素不要,后面的留下所以截取)
      let lyricObj = {} // 保存歌词的对象, key是秒, value是显示的歌词
      timeArr.forEach((item, index) => {
        // 拆分[00:00.000]这个格式字符串, 把分钟数字取出, 转换成秒
        let ms = item.split(':')[0].split('')[2] * 60
        // 拆分[00:00.000]这个格式字符串, 把十位的秒拿出来, 如果是0, 去拿下一位数字, 否则直接用2位的值
        let ss = item.split(':')[1].split('.')[0].split('')[0] === '0' ? item.split(':')[1].split('.')[0].split('')[1] : item.split(':')[1].split('.')[0]
        // 秒数作为key, 对应歌词作为value
        lyricObj[ms + Number(ss)] = contentArr[index]
      })
      // 返回得到的歌词对象
      return lyricObj
    }
    const audioStart = () => { // 播放按钮 - 点击事件
      console.log(audio.value)
      if (!data.playState) { // 如果状态为false
        audio.value.play() // 调用audio标签的内置方法play可以继续播放声音
      } else {
        audio.value.pause() // 暂停audio的播放
      }
      data.playState = !data.playState // 点击设置对立状态
    }
    const showLyric = () => {
      // 监听播放audio进度, 切换歌词显示
      audio.value.addEventListener('timeupdate', () => {
        let curTime = Math.floor(audio.value.currentTime)
        // 避免空白出现
        if (data.lyric[curTime]) {
          data.curLyric = data.lyric[curTime]
          data.lastLy = data.curLyric
        } else {
          data.curLyric = data.lastLy
        }
      })
    }
    onMounted(() => {
      getSong()
      showLyric()
    })
    return {
      audioStart,
      data,
      needleDeg,
      router,
      audio
    }
  }
}
</script>

<style scoped>
.header {
  height: 50px;
}

.play {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 1000;
}

.song-bg {
  background-color: #161824;
  background-position: 50%;
  background-repeat: no-repeat;
  background-size: auto 100%;
  transform: scale(1.5);
  transform-origin: center;
  position: fixed;
  left: 0;
  right: 0;
  top: 0;
  height: 100%;
  overflow: hidden;
  z-index: 1;
  opacity: 1;
  filter: blur(25px);
  /*模糊背景 */
}

.song-bg::before {
  /*纯白色的图片做背景, 歌词白色看不到了, 在背景前加入一个黑色半透明蒙层解决 */
  content: " ";
  background: rgba(0, 0, 0, 0.5);
  position: absolute;
  left: 0;
  top: 0;
  right: 0;
  bottom: 0;
}

.song-wrapper {
  position: fixed;
  width: 247px;
  height: 247px;
  left: 50%;
  top: 50px;
  transform: translateX(-50%);
  z-index: 10001;
}

.song-turn {
  width: 100%;
  height: 100%;
  background: url("./img/bg.png") no-repeat;
  background-size: 100%;
}

.start-box {
  position: absolute;
  width: 156px;
  height: 156px;
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  display: flex;
  justify-content: center;
  align-items: center;
}

.song-start {
  width: 56px;
  height: 56px;
  background: url("./img/start.png");
  background-size: 100%;
}

.needle {
  position: absolute;
  transform-origin: left top;
  background: url("./img/needle-ab.png") no-repeat;
  background-size: contain;
  width: 73px;
  height: 118px;
  top: -40px;
  left: 112px;
  transition: all 0.6s;
}

.song-img {
  width: 154px;
  height: 154px;
  position: absolute;
  left: 50%;
  top: 50%;
  overflow: hidden;
  border-radius: 50%;
  transform: translate(-50%, -50%);
}

.m-song-h2 {
  margin-top: 20px;
  text-align: center;
  font-size: 18px;
  color: #fefefe;
  overflow: hidden;
  white-space: nowrap;
  text-overflow: ellipsis;
}

.lrcContent {
  margin-top: 50px;
}

.lrc {
  font-size: 14px;
  color: #fff;
  text-align: center;
}

.left-incon {
  position: absolute;
  top: 10px;
  left: 10px;
  font-size: 24px;
  z-index: 10001;
  color: #fff;
}

.ani {
  animation: turn 5s linear infinite;
}

@keyframes turn {
  0% {
    -webkit-transform: rotate(0deg);
  }

  100% {
    -webkit-transform: rotate(360deg);
  }
}
</style>